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International Journal of Game Theory

, Volume 37, Issue 3, pp 307–320 | Cite as

Symmetric versus asymmetric equilibria in symmetric supermodular games

  • Rabah Amir
  • Michał Jakubczyk
  • Małgorzata Knauff
Original Paper

Abstract

This paper investigates the general properties of symmetric n-player supermodular games with complete-lattice action spaces. In particular, we examine the extent to which all pure strategy Nash equilibria tend to be symmetric for the general case of multi-dimensional strategy spaces. As asymmetric equilibria are possible even for strictly supermodular games, we investigate whether some symmetric equilibrium would always Pareto dominate all asymmetric equilibria. While this need not hold in general, we identify different sufficient conditions, each of which guarantees that such dominance holds: 2-player games with scalar action sets, uni-signed externalities, identical interests, and superjoin payoffs. Various illustrative examples are provided. Finally, some economic applications are discussed.

Keywords

Strategic complementarity Endogenous heterogeneity Symmetry breaking Doubly symmetric games Superjoin payoffs 

JEL Classification

C72 L13 

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Copyright information

© Springer-Verlag 2008

Authors and Affiliations

  • Rabah Amir
    • 1
  • Michał Jakubczyk
    • 2
    • 3
  • Małgorzata Knauff
    • 2
  1. 1.Department of EconomicsUniversity of ArizonaTucsonUSA
  2. 2.Warsaw School of EconomicsWarsawPoland
  3. 3.Department of PharmacoeconomicsMedical University of WarsawWarsawPoland

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